Fluid motor



'pril 7,` 1936.'

Nm. wm, -.wwmmw E gunman d mw R. /Z? f, E o

.IM i

ngmun Iza 06:72 for dll anstatt runnin Moron @arl l1". dibbe,Plz-adelphia, Pa., assigner to :were ican Engineering flompany, Padelpa,Pa., a corporation of Wennsylvania Application/May 2, i524, Serial No.222,252

l5 lClainns.

`vide aV generally improved and simplified valve mechanism for fluidmotors of the stated character which functions to permit fluid from thepressure side of the motor to bypass to the exhaust side thereof underpredetermined conditions, to

enualiue the pressure in the system and thus prevent shock or dage tothe operating parts.

another object is to provide in a fluid motor of the stated character anadjustable bypass element vvhich ls actuatedl to one position ofadjustment when the plungers approach their limit of travel in onedirection to permit fluid from the cylinders subjected to pressure tobypass to the cylinders connected to exhaust, and which is actuated toanother position of adjustment to permit Huid from the cylinderssubjected to pressure to bypass to the cylinders connected to exhaustwhen the plungers approach their limit of travel in the oppositedirection', to equalize the pressure in the system and thereby preventshocl'r or damage to the operating parts.

"A further object is to provide a. bypass valve construction of thestated character having a plurality of passages provided therein, one ofwhich is rendered effective when the motor plungers approach their limitof travel in one direction, and another of which is rendered effectivewhen the rams approach their limit of travel in the reverse direction,and to provide check valves in said passages which become effective toprevent a reverse now of fluid through said passages when equalizationof the pressures in the system has been eifected.

Other and further objects will become apparent as thedescriptlon of theinvention progresses.

Of the drawing:

Fig. l ls a plan view of the assembled construction including the bypassvalve unit comprising the present invention, and the operating mechanismtherefor. i

Fig. 2 is a sectional plan view of the bypass valve unit and a portionof the operating mechanism therefor.

(EL @tl-52) may be driven by an electric motor Il l or by any othersuitable driving means, and may be of the general type shown anddescribed ln the United States patent to Hele-Shaw 1,077,979, or of anyother suitable type.

in the present instance fluid motor l is employed to operate a rudder,the stock thereof being designated by the numeral l2. Rudder stock l2 issecured to a crosshead l2 having a pair f slots it and it provided atthe ends thereof which receive studs it and il secured to and extendingupwardly from rams t and 'l respectlvely. Pipes t and t are provided atone end thereof with i' couplings l2 and l5 respectively, to which areconnected branch pipes 2t and 2l which connect one end of cylinders 2and l with a bypass valve designated generally by the numeral 22.Cylinders 2 and 5 are connected to pipes 2 and 2 respectively, by branchpipes and 25, through 'l' couplings 22 and 2t.

Referring to Fig. 2, valve mechanism 22, it is seen, comprises asubstantially cylindrical casing 2l having a reciprocable valve member2t operating therein, and a pair of end plates 2li and 32 secured tocylinder 2l by bolts 3l and 32 respectively. Valve 221s substantiallycylindrical in construction and is provided with a pair of spacedpassages 33 and 34 having a pair of check valves 35 and 36 respectively,provided intermediate the ends thereof. Valves 35 and 35 are normallyheld upon their respective seats 31 and 32 by a pair of springs 39 and40. The stems 4l and 42 of valves 35 and 36, respectively, extendthrough and are guided in the cent1-albores of a pair of plugs 43 and44, which are secured in axially aligned tapped apertures provided atthe opposite ends of valve 28. The tension of springs 35 and 40 may bevaried by simply adjusting plugs 43 and 44.

Fig. 2 shows valve 2B in normal position wherein the solid portionthereof between passages 33 and 34 registers with apertures45 and 46provided in casing 21, which apertures communicate with branch pipes 20and'2i, respectively. Valve member 28 is held in its central position asshown in Fig.v 2, by a pair of springs and 5I provided at the left hand.end. thereof, and a pair of similar springs 52 and 53 provided at theright hand end thereof. Springs 5U and 5l extend between spring seats 54and 55 formed in the left hand end of valve member 22, and adjustablespring seats 56 and 5l. A pair of guide rods 58 and 53 are secured tothe left hand end of valve member 23 and the enlarged portions thereofextend thi ough the central bores lil of a pair of plugs 68 and 6|secured in tapped apertures provided in end plate 28. The annularshoulders 62 and 63 formed by the enlarged portion of rods 58 and 59engage spring seats 56 and 51 respectively, when valve member 28 isshifted to the right, to thereby retain the springs in proper position.Springs 52 and 53 likewise extend between spring seats 64 and 65provided in the right hand end of valve member 2l, and a pair ofadjustable spring seats 66 and 61. The tension of springs 52 and 53 maybe adjusted by a pair of plugs 68 and 69 secured in tapped aperturesprovided in end plate 30. A pair of guide rods 10 and 1| are secured tothe right hand end of valve member 28 and the enlarged portions thereofextend through the central bores provided in plugs 88 and 69. Theshoulders 12 and 13 formed by enlarged portions of said rods engagespring seats 66 and 61 when valve member 28 is shifted to the left tothereby retain springs 52 and 53, respectively, in proper position. Theouter ends of rods 10 and 1| are connected to a cross bar 14 to which aguide rod 15 is operatively connected. Rod 15 operates in a guidebearing 16, as shown in Fig. 1. The outer end of rod 15 is provided witha stud 11 which engages into a slot 18 provided in arm 18 of a bellcrank lever 80. Bell crank lever is pivoted to a xed support indicatedat 8|, and the other arm 82 thereof is bent so that the free end thereoflies substantially midway between the pair of adjustable bolts 83 and 84secured in a pair of ears 85 and 86 respectively projecting outwardlyfrom rudder stock l2, when crosshead I3 is in normal position. By thisarrangement, it is seen that when crosshead i3 approaches its limit oftravel in a clockwise direction bolt 84 will engage bell crank lever 88thereby rocking the latter in a counterclockwise direction which in turnactuates valve member 28 to the left, to bring passage 34 thereof intoalignment with pipes 28 and 2|. It is also seen that when crosshead I3approaches its limit of travelA in a counter clockwise direction, bolt83 will engage bell crank lever 80, thereby rocking the same in aclockwise direction to move valve member 28 to the right, bringingpassage 33 provided therein into alignment with pipes 20 and 2|. Inorder to insure proper operation of valve member 28 in the event thatuid should leak past valve member 28 and into the chambers at theopposite ends thereof a bypass pipe 81 is provided. By this constructionit is seen that any fluid contained in the chambers at the ends of valve28 will simply bypass from one end of the casing to the other uponmovement of said valve member.

From the foregoing description it is seen that when pump I0 is soadjusted as to deliver fluid pressure to cylinders 3 and 4, crosshead I3will move in a counter clockwise direction and that when said crossheadapproaches its limit of travel valve 28 will be shifted to the right(Fig. 2) as previously described, thereby aligning passage 33 thereofwith pipes 20 and 2|. Fluid pressure entering passage 33 from pipe 2|will then unseat check valve 35 and permit fluid to pass through passage34 into branch pipe 28 and thence to the ends of cylinders 2 and 5thereby equallzing the pressure in all the cylinders and causingcushioning of the rams and nal stoppage thereof. At this time pump Illhas been adjusted to neutral position. Mechanisms for controlling pumpsin this manner are well known in the art and for a full disclosure ofsuch a mechanism reference may be had to the United States patent to R.C. Lamond No. 1,986,640. When the pressure is equalized in this mannerspring 39 will urge check valve 35 upon its seat, and further passage offluid therethrough is prevented. Now, in the event that pump I0 were soadjusted as to deliver iiuid pressure to cylinders 2 and 5, check valve35 will be also Aheld upon its seat by the pressure entering passage 33through pipe 20 and acting upon the face of said valve. Crosshead |3will now move in a clockwise direction and when it approaches its limitof travel bolt 84 engaging bell crank lever 80 will shift valve 28 tothe left (Fig. 2) aligning passage 34 with branch pipes 20 and 2|. Fluidentering passage 34 from pipe 28 will now unseat check valve 36 andthereby permit fluid to also pass to cylinders 4 and 3, therebyequalizing the pressures in the system. At

this time pump I0 has again been adjusted to neutral as above described,and when the pressure has again become equalized spring l0 will urgecheck valve 36 upon its seat and further passage of fluid throughpassage 34 is thereby prevented. When crosshead I3 moves in the reversedirection from which it has been previously operated bringing bolts 83or 84 out of contact with bell crank lever 80, springs 50, 5| or 52, 53,as the case may be, will actuate valve member 28 to the neutral positionshown in Fig...

2. By providing the shoulders 62 and 63 on rods 58 and 59 it is seenthatwhen valve 28 is moved to the right springs 58 and 5| will also moveto the right and thus remain properly positioned upon their respectiveseats. The same isA f true in connection with springs 52 and 53. When'in which plugs 68, 6| and 68, 68 are secured tov further prevent leakageof fluid from the valve mechanism.

The valve member 28 may comprise but a single casting. The valve seats31 and 38 for check valves 35 and 36 respectively, may be machined bysimply inserting the tool through the apertures in which the plugs 43and 44 are secured. The casing enclosing the valve member 28 is also ofa simplifiedconstruction. It therefore is seen that the valve mechanismas a whole is not only of simplified construction but may bemanufactured at a relatively low cost.

The invention has been shown applied to a motor comprising a pair oframs, but it is believedy to be apparent that the invention is equallyapplicable to uid motors employing but a single ram. In such aconstruction the bypass valve 22 is simply placed in the pipe linesconnecting the ends of the cylinders with the pump and is operated bymovement of a crosshead similar to that shown herein. It is alsobelieved to be apparent that valve member 28 may be shifted to the rightor left upon movement of the rams through the instrumentality ofprojections provided on the rams themselves. Such a construction may bedesirable in installation where the crosshead is not in close proximityto the motor. The specific constructionof valve member 28,

aoaaaev as illustrated herein, may also talle other forms Withoutdeparting from the present invention.

it therefore is to be understood that the invention ls not to be limitedto the embodiment herein shown, since it may be embodied in other iorms,all eenling Within the scope of the claims `which. iollovv.

W11 `at is claimed is:

l. in a device oi the class described, the combination with a duidmotor, oi a bypass valve unit inted between the opposite ends of saidmotor, said unit comprising a casing, a valve member mounted in saidcasing apted for movement to diderent positions oi adjustment to petduid to ss trom the pressure end of the motor to e exhaust end thereofwhen said motor approaches its limit oi travel in either dlrection.

2. in a device oi the class described, the cornbinatlon with a uidmotor, of a bypass valve unit operatively connected to said motor, saidunit comprising a casing and a valve member ovable in said casing todiderent positions of adjustment, to permit fluid to pass from thepressure end oi the motor to the exhaust end thereoi when said motorapproaches its limit of travel in either direction, and means foractuating said valve member to inedective position.

d. lin a device oi the class described, the combination with' a duidmotor, of a bypass valve unit operativelyl connected to said motor, saidunit comprising a casing and a valve member movable in said casing todifferent positions of adjustment to permit fluid to pass from thepressure end oi the motor to the exhaust end thereof when said motorapproaches its limit of travel in either direction, and adjustableresilient means ior normally retaining said valve member in inedectlveposition.

d. in a device oi the class described, the combination with a uid motor,of a bypass valve unit operatively connected to said motor, said unitcomprising, a casing and a valve member movable in said casing, aplurality oi bypass means provided in said member, means for normallyretaining said member in ineffective position, means for moving saidmember to one position oi adjustment to render effective one of saidbypassmeans to permit fluid to bypass from the pressure end of saidmotor to the exhaust end thereoi when the motor approaches its' limit oftravel in one direction, and means ior moving said member to anotherposition of adjustment to render another of said bypass means effectiveto permit :duid to bypass from the pressure end of said motor to theexhaust end thereof when said motor approaches its limit of travel inthe reverse direction.

5. lin a device of the class described, the combination with a duidmotor, oi a bypass valve unit operatively connected to said motor, saidunit comprising a casing, and a valve member movable in said casing todiierent positions of adjustment, resilient means provided at either endoi said valve member for normally retaining the same in ineffectiveposition, means for moving said member to one of its positions oradjustment to permit fluid to bypass from the pressure end of the motorto the exhaust end thereoi when said motor approaches its limit oftrav'el in one direction, means for moving said member to anotherposition of adjustment to permit fluid to bypass from the pressure end fthe motor to the exhaust end thereof when said motor is operated in areverse direction, and means for retaining said resilient means inproper position during movement of said valve member.

\ 6. In a device of the class described, the combination with a fluidmotor, oi? a bypass valve unit operatively connected to said motor, saidunit comprising a casing, and a valve member movable in said casing, aplurality oi bypass means provided in said member, resilient meansprovided at either end of said valve member ior normally retaining thelatter in inedective position, means ior moving said member to one posi.

tion oi adjustment to render edective one of said bypass means to permitduid to bypass irom the pressure end of said motor to the exhaust endthereof when the motor approaches its limit of travel in one direction,means for moving said member to another position of adjustment to renderanother of said bypass means edective to permit fluid to bypass from thepressure end oi said motor 'to the exhaust end thereoi when said motorapproaches its limit oi travel in a reverse direction, said resilientmeans being adapted to actuate said valve member to inedective position,and means for retaining said resilient means in proper position duringoperation of said valve member.

7. in a vdevice of the class described, the combination with a rudderstocln'of a iiuid motor ior actuating said rudder stock, a bypass valve'unit operatively connected to said motor, said unit comprising acasing, and a valve member movable in said casing to different positionsoi' adjustment to permit iluid to pass from the pressure end of themotor to the exhaust end thereof when said motor approaches its limit oitravel in either direction, and means operatively connected to saidrudder sto'clr for actuating said valve member to diderent positions ofadjustment. i

8. lin a device of the class described, the combination with a rudderstock, of a fluid motor for actuating said rudder stock, a bypass valveunit operatively connected to` said motor, said unit comprising acasing, and a valve member movable in said casing, resilient means fornormally retaining said member in inedective pos-itam, means provided onsaid rudder stoclr for actuy ating said valve member to one position ofadjustment to permit fluid to pass from the pressure end of the motor tothe exhaust end thereof when said motor approaches its limit oi travelin one direction, and additional-means provided on said rudder stock foractuating said valve member to another position oi adjustment to permitiluid r to pass from the pressure end of said motor to the exhaust endthereof when said motor approaches its limit ci travel in the reversedirection.

9. in a device oi the class described, the combination with a rudderstock, oi a fluid motor ior actuating said rudder stock to differentpositions oi'v adjustment, a bypass valve unit operatively connected tosaid motor, said unit comprising a casing and a valve member movable insaid casing, a plurality oi bypass means provided in said` member, meansfor normally retaining said member in ineffective position, meansprovided on said rudder stock for moving said member to one position oradjustment to render effective one of said bypass means to permit fluidto bypass from the pressure end of said motor to the exhaust end thereofwhen the motor approaches its limit of travel :ln one direction, andadditional means provided on said rudder stock for moving said member toanother position of adjustment to render another of said bypass meanseffective to permit fluid to bypass from the pressure end oi said motorto the exhaust end thereof when said motor approaches its limit oftravel in the reverse direction.

10. In a device of the class described, the combination with a rudderstock, of a fluid motor for actuating said rudder stock to differentpositions of adjustment, said motor comprising, a ram, and a pair ofcylinders embracing the opposite ends of said ram, a bypass valve unitoperatively connected to the opposite ends of said motor, said unitcomprising a casing, and a valve member movable in said casing, meansfor moving said valve member to one position of adjustment to permitfluid to pass from the cylinder subjected to pressure to the cylinderconnected to exhaust when the ram is actuated in one direction, andadditional means for actuating said valve member to another position ofadjustment to permit uid to pass from the other of said cylinderssubjected topressure to the cylinder connected to exhaust when said ramis actuated in the reverse direction.

ll. In a device of the class described, the combination with a 'fluidmotor comprising, a pair of rams, cylinders embracing the opposite endsof each of said rams, piping connecting the cylinders of one of the ramswith the diagonally opposed cylinders of the other ram, a pump forsupplying fluid pressure to either of said connected pairs of cylinderswhile exhausting the other, a bypass valve unit operatively connected tosaid connected pairs of cylinders, said unit comprising a casing, avalve member movable in said casing to different positions ofadjustment, means for moving said valve member to one position ofadjustment to permit fluid to pass from the cylinders connected topressure to the cylinders connected to exhaust when said rams approachtheir limit of travel in one direction, and additional means foractuating said valve member to another position of adjustment to permitfluid to pass from the other of said cylinders subjected to pressure tothe cylinders connected to exhaust when said rams approach their limitof travel in the reverse direction.

12. In a device of the class described, the combination with a fluidmotor, of a bypass valve unit operatively connected to said motor, saidunit comprfsing a casing, and a valve member movable in said casing todifferent positions of adjustment, a plurality of bypass means providedin said valve member, a check valve provided in each of said bypassmeans to permit fluid passage therethrough in one direction only, meansfor normally retaining said member in ineffective position, means formoving said member to one position of adjustment to render effective oneof said bypass means to permit iluid to bypass from the pressure end ofsaid motor to the exhaust end thereof when the motor approaches itslimit of travel in one direction, and means for' moving said member toanother position of adjustment to render another of bypass meanseffective to permit fluid to bypass from the pressure end of said motorto the exhaust end thereof when said motor approaches its limit oftravel in the reverse direction.

13. In a device of the class described, the combination with a fluidmotor, of a valve unit operatlvely connected to said motor, said unitcomprising a substantially cylindrical casing, a valve aosaasv membermovable in said casing to different positions of adjustment, guide rodsfor said valve member, adjustable spring means for retaining said valvemember in normally ineffective position, one or more passages providedin said valve member, a check valve for each of said passages, wherebyfluid may pass therethrough in one direction only, adjustable means forurging said check valves upon their seats to normally prevent thepassage of fluid therethrough, means for actuating said valve member toone position of adjustment to render one of said passages effective topermit fluid to bypass from the pressure end of said motor to theexhaust end thereof when the motor approaches its limit of travel in onedirection, and means for actuating said valve member in the reversedirection to render another of said passages effective to permit fluidto bypass from the pressure end of said motor to the exhaust end thereofwhen said motor approaches its limit of travel in the reverse direction.

14. In a device of the class described, the combination with a fluidmotor, of a valve unit operatively connected to said motor, said unitcomprising a casing, a valve member operable in said casing to differentpositions of adjustment, said valve member having two or more passagesprovided therein in spaced relation, a check valve for each of saidpassages whereby fluid may pass therethrough in one direction only,means for actuating said valve member to one position to render one ofsaid passages effective while rendering the other passages ineffectiveto permit fluid-to bypass from the pressure end ofsaid motorto theexhaust end thereof when the motor approaches its limit of travel in onedirection, means for actuating said valve member to another position ofadjustment to render another of said passages effective while renderingsaid first mentioned passage ineffective to permit fluid to bypass fromthe pressure end of said motor to the exhaust end thereof, when themotor approaches its limit of travel in the reverse direction, andresilient means for actuating said valve unit to normal position wherebyall of said passages are rendered ineffective.

15. In a device of the class described, the combination with a fluidmotor, of a bypass valve unit operatively connected to said motor, saidunit comprising a casing, a valve member operative in said casing todifferent positions of adjustment, guide rods for said valve member,adjustable spring means for retaining said valve member in normallyineffective position, two or more passages provided in said valve memberin spaced relation, a check valve for each of said passages wherebyfluid may pass therethrough in one direction only, means for actuatingsaid Valve member in one direction to render one of said passageseffective to permit fluid to bypass from the pressure end of said motorto the exhaust end thereof when the motor approaches its limit of travelin one direction, means for actuating said valve member to anotherposition of adjustment to render another of said passages effective topermit fluid to bypass from the pressure end of said motor to theexhaust end thereof when the motor approaches its limit ff travel in thereverse direction, and means provided on said guide rods for bodilymoving said spring means when said valve member is adjusted to therebyretain the same in proper position.

ICARL F. SIBBE.

